The Betabeam http:betabeam.web.cern.chbetabeam

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The Beta-beamhttp//beta-beam.web.cern.ch/beta-be
am/

• Mats Lindroos
• on behalf of the
• The beta-beam study group

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CERN b-beam baseline scenario
SPL
Decay ring Brho 1500 Tm B 5 T Lss 2500 m
SPS
Decay Ring
ISOL target Ion source
ECR
Cyclotrons, linac or FFAG
Rapid cycling synchrotron
PS
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Beam parameters in the decay ring

• 18Neon10 (single target)
• Intensity 4.5x1012 ions
• Energy 55 GeV/u
• Rel. gamma 60
• Rigidity 335 Tm

• 6Helium2
• Intensity 1.0x1014 ions
• Energy 139 GeV/u
• Rel. gamma 150
• Rigidity 1500 Tm

• The neutrino beam at the experiment should have
  the time stamp of the circulating beam in
  the decay ring.
• The beam has to be concentrated to as few and as
  short bunches as possible to maximize the number
  of ions/nanosecond. (background suppression)

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6He production by 9Be(n,a)
Converter technology (J. Nolen, NPA 701 (2002)
312c)
Layout very similar to planned EURISOL converter
target aiming for 1015 fissions per s.
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Production of b emitters

• Scenario 1
• Spallation of close-by target nuclides18,19Ne
  from MgO and 34,35Ar in CaO
• Production rate for 18Ne is 1x1012 s-1 (with 2.2
  GeV 100 mA proton beam, cross-sections of some mb
  and a 1 m long oxide target of 10 theoretical
  density)
• 19Ne can be produced with one order of magnitude
  higher intensity but the half life is 17 seconds!
• Scenario 2
• alternatively use (?,n) and (3He,n) reactions
• 12C(3,4He,n)14,15O, 16O(3,4He,n)18,19Ne,
  32S(3,4He,n)34,35Ar
• Intense 3,4He beams of 10-100 mA 50 MeV are
  required

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60-90 GHz  ECR Duoplasmatron  for gaseous RIB
2.0 3.0 T pulsed coils or SC coils
Very high density magnetized plasma ne 1014 cm-3
Very small plasma chamber F 20 mm / L 5 cm
Target
Arbitrary distance if gas
Rapid pulsed valve

• 1-3 mm
• 100 KV
• extraction

60-90 GHz / 10-100 KW 10 200 µs / ? 6-3
mm optical axial coupling
UHF window or  glass  chamber (?)
20 100 µs 20 200 mA 1012 to 1013 ions per
bunch with high efficiency
Moriond meeting Pascal Sortais et
al. LPSC-Grenoble
optical radial coupling (if gas only)
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Overview Accumulation

• Sequential filling of 16 buckets in the PS from
  the storage ring

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Overview Decay ring

• Ejection to matched dispersion trajectory
• Asymmetric bunch merging

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Asymmetric bunch merging
S. Hancock
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Asymmetric bunch merging
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Decay losses

• Losses during acceleration are being studied
• Full FLUKA simulations in progress for all stages
  (M. Magistris, CERN-TIS)
• Preliminary results
• Can be managed in low energy part
• PS will be heavily activated
• New fast cycling PS?
• SPS OK!
• Full FLUKA simulations of decay ring losses
• Tritium and Sodium production surrounding rock
  well below national limits
• Reasonable requirements of concreting of tunnel
  walls to enable decommissioning of the tunnel and
  fixation of Tritium and Sodium

A. Jansson
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SC magnets

• Dipoles can be built with no coils in the path of
  the decaying particles to minimize peak power
  density in superconductor
• The losses have been simulated and a first dipole
  design has been proposed

S. Russenschuck, CERN
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Tunnels and Magnets

• Civil engineering costs Estimate of 400 MCHF for
  1.3 incline (13.9 mrad)
• Ringlenth 6850 m, Radius300 m, Straight
  sections2500 m
• Magnet cost First estimate at 100 MCHF

FLUKA simulated losses in surrounding rock (no
public health implications)
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Intensities
Only b-decay losses accounted for, add efficiency
losses (50)
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Conclusions

• Physics
• Super beam, beta-beam and FREJUS WORLD unique
• Low energy beta-beam Nuclear Physics!
• Design study proposal as part of EURISOL is now
  being prepared
• You are welcome to join (contact
  Mats.Lindroos_at_cern.ch or Michael.Benedikt_at_cern.ch)
  
• New ideas are being further studied and could
  give very important improvements to the physics
  reach
• Workshop on Exploring the Impact of New Neutrino
  Beams, ECT, Trento, Italy, 18-22 October 2004,
  (C. Volpe, J. Bouchez, M. Lindroos, M. Mezzetto,
  T. Nilsson)

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Collaborators

• The beta-beam study group
• CEA, France Jacques Bouchez, Saclay, Paris
  Olivier Napoly, Saclay, Paris Jacques Payet,
  Saclay, Paris
• CERN, Switzerland Michael Benedikt, AB Peter
  Butler, EP Roland Garoby, AB Steven Hancock, AB
  Ulli Koester, EP Mats Lindroos, AB Matteo
  Magistris, TIS Thomas Nilsson, EP Fredrik
  Wenander, AB
• Geneva University, Switzerland Alain Blondel
  Simone Gilardoni
• GSI, Germany Oliver Boine-Frankenheim B. Franzke
  R. Hollinger Markus Steck Peter Spiller Helmuth
  Weick
• IFIC, Valencia Jordi Burguet Juan-Jose
  Gomez-Cadenas Pilar Hernandez
• IN2P3, France Bernard Laune, Orsay, Paris Alex
  Mueller, Orsay, Paris Pascal Sortais, Grenoble
  Antonio Villari, GANIL, CAEN Cristina Volpe,
  Orsay, Paris
• INFN, Italy Alberto Facco, Legnaro Mauro
  Mezzetto, Padua Vittorio Palladino, Napoli Andrea
  Pisent, Legnaro Piero Zucchelli, Sezione di
  Ferrara
• Louvain-la-neuve, Belgium Thierry Delbar Guido
  Ryckewaert UK Marielle Chartier, Liverpool
  university Chris Prior, RAL and Oxford university
  
• Uppsala university, The Svedberg laboratory,
  Sweden Dag Reistad
• Associate Rick Baartman, TRIUMF, Vancouver,
  Canada Andreas Jansson, Fermi lab, USA